Effects of Type and Breed of British, Zebu and Dairy Cattle on Production, Palatability and Composition. I. Rate of Gain, Feed Efficiency and Factors Affecting Market Value2

Abstract

Over a 5-year period, a total of 154 steers of six breeds and one cross representing British, Zebu and dairy breeding were fullfed under similar environmental conditions. Differences among years were significant for 21 of the 23 traits statistically analyzed and probably were partially due to differing sources of steers and feeding methods. Significant type effects were observed for all traits except daily gain. Of the two British breeds, Angus steers graded significantly higher at the time they were taken off feed and dressed significantly higher. Their carcasses also graded significantly higher, and possessed more marbling and kidney fat; whereas, Hereford carcasses had significantly longer loins and legs, and plumper rounds. Hereford steers gained slightly faster in the feedlot with a higher feed efficiency. Both British breeds graded significantly higher, were fatter and had shorter carcasses, legs and loins than other breeds. Within the three groups containing at least 37% Brahman breeding, straight Brahman steers had significantly lower off-feed, shrunk slaughter and warm carcass weights, were on feed longest, and had lower daily gains, slaughter grades and carcass grades than Santa Gertrudis or Braham-British crosses. The latter two groups did not vary significantly in any production or carcass trait studied. The two dairy breeds, Holstein and Jersey, differed significantly in all traits except those involving grade, shrinkage and fatness. Holstein steers gained fastest of all breeds on less feed but dressed lowest of all breeds except Jerseys. Holstein carcasses graded lowest, had the least marbling and external fat covering, were deepest in the chest and longest-legged of all breeds. Jersey carcass measurements indicated that this breed was the most angular and thinly-fleshed. Jersey carcasses combined the greatest amount of kidney fat (6.5%) with next to the lowest grade and external fat cover (4.5 mm.). Angus carcasses were fattest externally (13.3 mm.) and had the second largest kidney knob (5.0%). Breed apparently influences the relationship between external and internal fat deposition.